Is there some medical reason why you need to take potassium supplements? If so, your doctor should determine what your need is. If there's no medical reason, there are lots of good foods that contain potassium. Some foods are actually high in potassium.
Is there some reason why you can't get your potassium from natural whole foods?
Dry beans, lentils and split peas are all good sources of potassium and are very inexpensive. You can get a one pound bag of lentils for under a dollar and it will make several meals (I never really counted how many). If you add some inexpensive whole grain rice to the lentils, you'll get complete protein. Then you won't need to buy meat which usually costs a lot more.